The present invention relates to compositions for inhibiting the deposit of scale from aqueous solutions, and more particularly, the invention relates to scale-inhibiting compositions and the like containing fluorocarbon compounds and which can also contain conventional boiler compounds, such as organophosphates, together with methods for preventing the deposition of scale from aqueous solutions.
Salt deposits, and particularly calcium carbonate deposits, can turn out to be very troublesome, particularly in the following areas:
Desalination of seawater by distillation,
Commercial refrigeration, and
Distribution and usage of domestic water.
There is accordingly a commercial need to provide materials which inhibit scale deposits.
A number of scale-inhibiting, or boiler, compounds have been proposed. Among these are polyphosphates, organophosphates, and polyelectrolytes. The polyphosphates have a drawback in that they are liable to hydrolyze in aqueous solutions, so that their effectiveness is greatly diminished, and moreover they are relatively toxic. The organophosphates and the polyelectrolytes often have little or no efficacy.
The anti-scaling activity of an inhibiting compound involves either a diminution of the crystal growth rate, inhibition of the homogeneous germination mechanisms (that is, the appearanace of crystals in the liquid phase), or the inhibition of heterogeneous germination mechanisms (that is, the appearance of crystals on surfaces).